Discovery Channel will air the event live, during which Wallenda will walk 1,500 feet above the Little Colorado River, a height greater than the Empire State Building. That's more than 1,300 feet higher than his history-making Niagara Falls walk, which aired live on ABC in June 2012.

Wallenda, known as "The King of the High Wire" and part of the legendary "Flying Wallendas" family, has said the walk will be the fulfillment of a lifelong dream to walk at such a great height as well as a chance to honor his great-grandfather, the legendary Karl Wallenda, who died after falling from a tightrope in Puerto Rico in 1978.

But there's a big difference between this walk and his Niagara walk: He won't be wearing a tether this time. Still, during a recent visit to The Hollywood Reporter's Cover Lounge, Wallenda said he doesn't get scared when attempting such a risky stunt.

"I think you have a choice," he said. "You can decide whether you want to get scared by something or not. You can go into a haunted house with the mindset of, 'This is going to freak me out,' or go into the haunted house with the mindset of, 'Who cares; this is all set up; it’s all gimmicks and it’s not going to scare me at all.'"

Still, he says he there are "definitely butterflies, definitely nerves, definitely respect, which is very important. When you do what I do, you've got to respect it. It is, no pun intended, a life on the line."

Wallenda said every precaution will be put into place to ensure his safety. On June 6, Wallenda and his team set up a training camp to simulate the conditions of walking over the Grand Canyon (the walk will take place in a remote section operated by the Navajo Nation Parks and Recreation). He said winds can reach up to 40 miles an hour in that location.

"It’s not as though I get on that wire, and it’s whatever happens, happens," he added. "I’ve actually trained my whole life that if something happens I grab that wire right away."

He's also trained to be able to hold onto the wire 15 to 20 minutes at a time, and said rescue teams will be able to get to him in less than a minute, no matter where he is on the two-inch-thick wire.

"I’m not the type of daredevil that’s like, 'Well, I’m going to try something that’s never been done before; let’s see what happens,'" he said. "There’s a lot of studies, honestly years of studies that go into this stuff."

Wallenda added that the fact the event will be televised live give viewers an additional thrill.

"There’s danger there, just like a NASCAR race," he said. "You’re watching, hoping there’s not an accident, but if there is, you want to see it. And I think that’s a lure as well. It’s the fact that it is dangerous, but they’re going to see me live, walking across without any safety whatsoever, you know 1,500 feet above that canyon floor."

Wallenda has a wife and three kids -- ages 15, 12 and 10 -- but he said that, while his wife gets nervous, she "understands my passion" and his love of performing.

Skywire Live With Nik Wallenda airs live at 8 p.m. ET/5 p.m. PT on Sunday on the Discovery Channel. Click here for more of THR's interview with Wallenda.